<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<style>
    *{
        padding:0;
        margin: 0;
        box-sizing: border-box;
    }
    .container{
        display: flex;

    }
    .box{
        float: left;
        margin-bottom: 5px;
        
        width: 50%;
        height: 100px;
        padding: 5px;
        background-color: #008000;
    }
</style>
<body>
<div class="container">
    <div class="box"></div>
    <div class="box"></div>
</div>
</body>
</html>